The present invention relates to a capsule for hygienically preparing a nutritional product containing nutritional ingredients by mixing the ingredients with a liquid; the capsule containing a filter filtering the liquid supplied in the capsule for removing undesired components contained in the liquid. The invention more particularly relates to a capsule for insertion in a device for supplying liquid in the capsule for preparing a nutritional product by mixing with the nutritional ingredients such as an infant formula, growing-up formula or adult nutrition formula. The invention also relates to a method using such capsule.
Nutritional compositions can be, for instance, infant formulas or also nutritional liquids for toddlers, invalids, elderly people, persons having nutritional deficiencies or athletes. These compositions are prepared from ingredients contained in a capsule by addition of a liquid such as water. The liquid may contain undesired contaminants such as micro-organisms and/or solid particles (e.g., dust, minerals, organic residues, etc.). These undesired contaminants should be removed from the liquid before the liquid is mixed with the ingredients to ensure an hygienic and safe preparation of the composition.
Therefore, there is a need for a capsule which enables preparation of nutritional composition for instance an infant formula or other food compositions in a convenient and safe manner.
WO2006/077259 discloses a method for preparing a single serving of a nutritional composition comprising introducing liquid such as water into a cartridge containing a unit dose of the composition in concentrated form. Thereby, the water is treated prior to the introduction into the cartridge in order to remove pathogens from the water. This treatment may be for instance a pre-heating, a filtering or an irradiation of the water with ultra-violet light.
WO 2008/012314 relates to a device which teaches the principle of treating water by means of a filter used for the preparation of nutritional compositions from a capsule inserted in a dispenser.
WO2009/115475 relates to a capsule for the preparation of a liquid comprising a puncturable delivery wall.
A capsule with an integrated antimicrobial filter has been described in WO 2009/092629 and No. 09156782.6 filed on 31 Mar. 2009.
The antimicrobial filter is preferably a thin microporous membrane which requires extremely precautionary measures when handling and positioning in the capsule during manufacturing. Handling of the filter itself should be controlled in order to avoid beforehand contamination. Furthermore, a reliable positioning and connection of the filter in the capsule must be assured to avoid any filtering defect during beverage preparation. Therefore, handling of the filter should be facilitated by a solution which is adapted to mass production whereby ensuring elevated hygiene and quality standards.
Furthermore, there is also a need for optimizing the use of packaging (i.e., non-food) materials in the capsule without detriment to the resistance of the capsule to the positive liquid pressure reigning in the capsule and preferably to provide a more environmentally friendly and cost effective product.
Another requirement is to ensure the release of the dedicated amount of the nutritional composition contained in the capsule to ensure a complete feed for each capsule, e.g., to the baby or child. No significant amount of nutritional liquid should be left in the capsule, most preferably, the capsule should be emptied from any liquid and solids. For this, the filter in the capsule can create a too high resistance to the pressurized gas (e.g., air) injected in the capsule during the emptying operation. As a result, the pressure of gas can be insufficient to properly empty the capsule or a too high pressure of gas is required which has an impact on the complexity and cost of the system.
Another requirement is to ensure that there is no contact during emptying of the capsule, i.e., between the gas opening device for the gas purge and contaminated liquid, e.g., nutritional ingredients or liquid, which would otherwise require systematic cleaning and so a clean-in-place system which would render the device more complex.
Another requirement is to ensure that the filter can support the deformation under the pressure of liquid supplied in the capsule, in particular, the pressure at the upstream surface of filter.